The present invention relates to balloon catheters and, more particularly, to a non-shortening wrapped balloon configured to expand with essential radial symmetry to a predetermined diameter upon application of a predetermined pressure thereto.
Balloon catheters are well known in the art. Such catheters are employed in a variety of medical procedures, including dilation of narrowed blood vessels, placement of stents and other implants, temporary occlusion of blood vessels, and other vascular uses.
In a typical application, the balloon is advanced to the desired location in the vascular system. The balloon is then pressure-expanded in accordance with a medical procedure. Thereafter, the pressure is removed from the balloon, allowing the balloon to contract and permit removal of the catheter. It is to be appreciated that the balloon is usually formed of an elastomeric material which is readily pressure-expanded, yet will also readily contract upon removal of the inflation pressure.
Procedures such as these are generally considered minimally invasive, and are often performed in a manner which minimizes disruption to the patient's body. As a result, catheters are often inserted from a location remote from the region to be treated. For example, during angioplasty procedures involving coronary vessels, the balloon catheter is typically inserted into the femoral artery in the groin region of the patient, and then advanced through such vessel into the coronary region of the patient. It is also common to have the length of the balloon change during inflation causing placement problems during procedures. Additionally, catheters have been unable to deliver balloons with large diameter expansion capability due to the need for a low profile and sustained pressures.
The present invention provides an improvement in balloon sealing techniques and reduction in seal profiles. Further, it is believed that further improvements in balloon performance can be achieved by modifying the mounting techniques, such as to provide a controlled failure mechanism.